This is a chance, to watch an event, which occurs roughly twice in
a decade. If you have missed the last one, here you may follow the tiny
innermost planet apparently moving over the suns photosphere, which boils
visibly in the elapsing time. The diameter ratio is nearly the real one,
because Mercury is not much nearer than the sun to Earth during such an
inner conjunction. There are several clips available, watch out for the
sizes... Besides, the tilt of the orbits of Mercury and Earth against each
other is responsible, that in most cases Mercury passes our sun "above
or below" suns disk, seen from our planet. Also further links to other
sites are provided.

One final remark: in 2004 a much more seldom event will take place,
a transit of our neighbor planet Venus. In the 20th century absolutely
NO such transit happened, and since the 19th century this and the 2012
event are the first we can witness! Compared with this, even total solar
eclipses are frequent occasions! And a Venus transit is much more spectacular
than a Mercury transit, due to Venus' larger size, lower distance from
Earth and the presence of a considerable atmosphere.

The only means to penetrate the optically never transparent atmosphere
of our planetary neighbor is Radar. And the Magellan orbiter did just that:
at this site you can work through the "pictures" (more precisely: computer
generated maps from the Radar data) of Venus' surface; there is really
much to observe, because the terrain is larger than the Earths continents
(Venus features no oceans, which cover the larger part of Earth). These
data will remain the global reference framework probably for a long time.
If you are unsure, how to use the interface, simply read the help page(s).

In this case the pictures are usual ones, and this is a place, to watch
the more or less known diverse parts of the Martian surface. You may zoom
in and out and of course choose from overview maps, where you want to get
a closer look. The Viking orbiter data were already detailed; the Mars
Global Surveyor will peak even much more deep inside these details.

This one can be of practical interest only for people, which are still
children at now, and only in the most optimistic case --- but because planning takes a rather long
time for such big and complex projects, it has to be done also long before. This
site describes in many details this ambitious project.

A small number of other animations, mostly not too big in size even
for not very well equipped and/or patient users. Some are "only" the outcome
of massive number crunching on fast computers, but should give nonetheless
an adequate impression from the real phenomena.

Here you can check out, if there are polar lights to expect due to increased
solar activity (especially from now (2000) to the next few years (around up to
2003)) or eventually havoc could be threat, because intense CMEs (coronal mass
ejections) can endanger electromagnetic devices, especially for communication,
and also any people in the Earths orbit (Shuttle, ISS, Mir).